**Core Concept**
A lumbar puncture (LP) is a procedure to collect cerebrospinal fluid (CSF) from the subarachnoid space surrounding the spinal cord. It is typically performed at the level of the lumbar cistern, where the spinal cord ends and the cauda equina begins, to minimize the risk of spinal cord injury.

**Why the Correct Answer is Right**
The correct level for a lumbar puncture is between L3-L5, with L4-L5 being the most common site. This is because the spinal cord ends at the level of L1-L2 in adults, and the dura mater, which contains the CSF, is more easily accessed at the lower lumbar levels. The L4-L5 interspace is chosen because it is usually the most dependent part of the spinal canal, making it easier to insert the needle and reduce the risk of complications.

**Why Each Wrong Option is Incorrect**
**Option A:** L1-L2 is too high, as the spinal cord ends at this level, and the risk of spinal cord injury is increased.
**Option B:** T10-T12 is too low, as the abdominal contents and iliac crest may interfere with the procedure.
**Option C:** C1-C2 is the cervical spine, which is not suitable for lumbar puncture due to the presence of the spinal cord.

**Clinical Pearl / High-Yield Fact**
When performing a lumbar puncture, it is essential to identify the correct interspace by palpating the spinous processes and feeling for the "dimples of Venus" (the interspinous spaces) to ensure accurate placement of the needle.

**Correct Answer: D. T10-T12 is too low, as the abdominal contents and iliac crest may interfere with the procedure.**